I'm building and na bridge port for my little starlet race car at the moment, the engine is based around an s4 fc3s engine but with hi comp rotors and what not. The question I have is I see a lot of n/a rotarys with the line between the back of the water pump and the rear iron blocked but a few with them linked with a piece of hose. What was this for on the turbo motors? Will it cause issues if I block it?
Thank you!

 

In stock form, that line provides coolant to the BAC/throttle body.

You can block them off if you like. People run a line from one to the other because they are too lazy to tap and plug the stock nipples.

 

Thank you!

 

Necro bump, I apologize. But I'm coming into this car with a bunch of stuff done. The hose pictured that looks squished I assume is serving this purpose and just looping the coolant?

 

yes. that's the one.